diff options
Diffstat (limited to 'src/basic/smack-util.c')
| -rw-r--r-- | src/basic/smack-util.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/src/basic/smack-util.c b/src/basic/smack-util.c new file mode 100644 index 0000000000..2e24b1ea99 --- /dev/null +++ b/src/basic/smack-util.c @@ -0,0 +1,208 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2013 Intel Corporation + + Author: Auke Kok <auke-jan.h.kok@intel.com> + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <sys/xattr.h> + +#include "util.h" +#include "process-util.h" +#include "path-util.h" +#include "fileio.h" +#include "smack-util.h" + +#define SMACK_FLOOR_LABEL "_" +#define SMACK_STAR_LABEL "*" + +bool mac_smack_use(void) { +#ifdef HAVE_SMACK + static int cached_use = -1; + + if (cached_use < 0) + cached_use = access("/sys/fs/smackfs/", F_OK) >= 0; + + return cached_use; +#else + return false; +#endif +} + +int mac_smack_apply(const char *path, const char *label) { + int r = 0; + + assert(path); + +#ifdef HAVE_SMACK + if (!mac_smack_use()) + return 0; + + if (label) + r = lsetxattr(path, "security.SMACK64", label, strlen(label), 0); + else + r = lremovexattr(path, "security.SMACK64"); + if (r < 0) + return -errno; +#endif + + return r; +} + +int mac_smack_apply_fd(int fd, const char *label) { + int r = 0; + + assert(fd >= 0); + +#ifdef HAVE_SMACK + if (!mac_smack_use()) + return 0; + + if (label) + r = fsetxattr(fd, "security.SMACK64", label, strlen(label), 0); + else + r = fremovexattr(fd, "security.SMACK64"); + if (r < 0) + return -errno; +#endif + + return r; +} + +int mac_smack_apply_ip_out_fd(int fd, const char *label) { + int r = 0; + + assert(fd >= 0); + +#ifdef HAVE_SMACK + if (!mac_smack_use()) + return 0; + + if (label) + r = fsetxattr(fd, "security.SMACK64IPOUT", label, strlen(label), 0); + else + r = fremovexattr(fd, "security.SMACK64IPOUT"); + if (r < 0) + return -errno; +#endif + + return r; +} + +int mac_smack_apply_ip_in_fd(int fd, const char *label) { + int r = 0; + + assert(fd >= 0); + +#ifdef HAVE_SMACK + if (!mac_smack_use()) + return 0; + + if (label) + r = fsetxattr(fd, "security.SMACK64IPIN", label, strlen(label), 0); + else + r = fremovexattr(fd, "security.SMACK64IPIN"); + if (r < 0) + return -errno; +#endif + + return r; +} + +int mac_smack_apply_pid(pid_t pid, const char *label) { + +#ifdef HAVE_SMACK + const char *p; +#endif + int r = 0; + + assert(label); + +#ifdef HAVE_SMACK + if (!mac_smack_use()) + return 0; + + p = procfs_file_alloca(pid, "attr/current"); + r = write_string_file(p, label); + if (r < 0) + return r; +#endif + + return r; +} + +int mac_smack_fix(const char *path, bool ignore_enoent, bool ignore_erofs) { + +#ifdef HAVE_SMACK + struct stat st; +#endif + int r = 0; + + assert(path); + +#ifdef HAVE_SMACK + if (!mac_smack_use()) + return 0; + + /* + * Path must be in /dev and must exist + */ + if (!path_startswith(path, "/dev")) + return 0; + + r = lstat(path, &st); + if (r >= 0) { + const char *label; + + /* + * Label directories and character devices "*". + * Label symlinks "_". + * Don't change anything else. + */ + + if (S_ISDIR(st.st_mode)) + label = SMACK_STAR_LABEL; + else if (S_ISLNK(st.st_mode)) + label = SMACK_FLOOR_LABEL; + else if (S_ISCHR(st.st_mode)) + label = SMACK_STAR_LABEL; + else + return 0; + + r = lsetxattr(path, "security.SMACK64", label, strlen(label), 0); + + /* If the FS doesn't support labels, then exit without warning */ + if (r < 0 && errno == EOPNOTSUPP) + return 0; + } + + if (r < 0) { + /* Ignore ENOENT in some cases */ + if (ignore_enoent && errno == ENOENT) + return 0; + + if (ignore_erofs && errno == EROFS) + return 0; + + r = log_debug_errno(errno, "Unable to fix SMACK label of %s: %m", path); + } +#endif + + return r; +} |